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Daniel A. Heinrich Anne C. Avery Michael S. Henson Jed A. Overmann Aaron K. Rendahl Jillian Z. Walz Davis M. Seelig 《Veterinary and comparative oncology》2019,17(3):365-375
Minimally invasive techniques used to evaluate canine peripheral lymphadenopathy (PLN), including fine needle aspiration biopsy with cytological evaluation (FNAB‐C) and flow cytometry (FC), have benefits and limitations. The cell block (CB) method is an alternate processing technique in which fine needle aspirate biopsy samples are concentrated, fixed, and embedded in paraffin for routine histological processing/staining. Utilizing three observers, we determined the diagnostic value of the CB in evaluating canine PLN across six categories (non‐diagnostic, reactive, inflammatory/infectious, probable lymphoma and lymphoma, metastatic neoplasia) and correlated findings to immunophenotypic and clonal antigen receptor rearrangement results in canine nodal lymphoma. Eighty‐five paired FNAB‐C and CB samples were evaluated from canine patients presenting to the University of Minnesota Veterinary Oncology or Internal Medicine services. Diagnostic quality samples were obtained in 55/85 (65%) CB and 81/85 (95%) FNAB‐C samples, respectively, and nodal pathology impacted CB diagnostic yield. Overall percent agreement between diagnostic‐quality FNAB‐C and CB samples was 86%, but increased to 95% if the categories of lymphoma and probable lymphoma were combined. There was 100% agreement for both the diagnoses of metastatic neoplasia and reactive lymph nodes and 92% agreement for the diagnosis of lymphoma/probable lymphoma. Using immunohistochemistry (IHC), CB samples correctly immunophenotyped 22/23 (96%) cases of B‐cell lymphoma, but only 1/6 (17%) cases of T‐cell lymphoma. IHC was not completed on nine cases of lymphoproliferative disease because of insufficient cellularity. When the CB method (CBM) yielded diagnostic quality samples there was good to excellent agreement with FNAB‐C samples and CB samples were suitable for some IHC tests. 相似文献
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The widely-used Silva-Bremner method for determining non- exchangeable NH4?N in the soil was modified so as to reduce reagent requirement and the time taken to carry out the analyses. In the modification, boiling the mixture of soil and KOBr on a hot plate was replaced with heating the soil/KOBr mixture, directly placed in centrifuge tubes, in a boiling water bath or a microwave oven. The best procedure is to keep the soil/KOBr mixture for 10 minutes in the water bath or for 10 minutes at 50% of full power in a microwave oven. The modified method gave similar values to the standard method on 4 quite different soils and also slightly increased reproducibility. 相似文献
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Karl Heinrich Hartge 《植物养料与土壤学杂志》2001,164(3):247-252
Soil as a volume — means to record its changes on profile basis Compaction and loosening of soils always means change of its total volume. Since such changes cannot occur downward, or sideways beyond the effect of closing cracks after previous shrinkage, the total effect is a change in the level of the soil surface. Such changes can be assessed by aid of the void ratio‐depth relation. This function is treated as an analogy to the compression curve of classical soil mechanics as obtained by 1‐dimensional confined oedometer measurement. It was termed as packing characteristic in earlier papers. Starting at this curve the solid volume for a freely chosen depth/vertical stress level in the soil column is calculated to be used as reference level. To this column the related height of pores is added which is calculated from the void‐ratio/vertical stress diagram. By this method the upper end of this calculation has to be chosen to be e.g. ca. 0.4 cm below proper surface. Using this procedure volume i.e. height changes can be compared for deliberately chosen soil profiles, fresh sediments, and artificial land fills. An important item for the precision of the result is the correctness of the assumption for linearity of the packing characteristic. This assumption was tested using sets of values from 63 soils. The observed deviations are interpreted in terms of mechanisms that may cause them. 相似文献
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Darío Martín-Benito Miren Del Río Ingo Heinrich Gerhard Helle Isabel Cañellas 《Forest Ecology and Management》2010
Thinning is the main forestry measure to increase tree growth by reducing stand tree density and competition for resources. A thinning experiment was established in 1993 on a 32-year-old Pinus nigra Arn. stand in central Spain. The response of growth, climate-growth relationships and intrinsic water use efficiency (WUEi) to a stand density reduction were compared between moderate thinned plots and a control plot by a combined analysis of basal area increments (BAI), and C and O stable isotope ratios (δ13Cc and δ18Oc). BAI in the control plot showed a decreasing trend that was avoided by thinning in the thinned plot. Thinning also partially buffered tree-ring response to climate and trees were less sensitive to precipitation although more sensitive to temperature. Δ13Cc in the thinned plot was not modified indicating that stomatal conductance (g) and photosynthetic capacity (A) did not change or change in the same direction. However, δ18Oc decreased in the control plot (unrelated to δ18O of precipitation) but not in the thinned plot, suggesting a relative increase of temperature and irradiance and/or a decrease of air humidity after reducing the density consistent with an increase in A, g and BAI. As WUEi did not increase in the thinned plot, faster growth in this plot was caused by higher abundance of resources per tree. The trend of WUEi in both plots indicated low-moderate CO2-induced improvements. Thinning might be a useful adaptation measure against climate change in these plantations reducing their vulnerability to droughts. However, because WUEi was not affected, the positive growth response might be limited if droughts and warming continue and certain thresholds are exceeded. 相似文献